Code review comment for lp://staging/~taihsiangho/ubiquity/trusty-proposed

@ Dimitri

I wish that I could automate oem installation which comes with ubuntu-recovery.

In some customized images, for example OEM images, some of them have already use oem-config-general.sh. This means oem-config/early_command and oem-config/late_command are not a universal solutions because the hook, oem-config-general.sh, may be used by others at the beginning when that image was built. We could not just put our own.

We have tried to preseed oem-config/early_command and oem-config/late_command at stage 1 installation to use our own script which could include oem_config.sh and oem-config-general.sh,
but both of them will be overwritten by ubuntu-recovery anyway.[1]
We can not actually use our own oem-config/early_command and oem-config/late_command script.

We need a another hook or way to hook up our own customized scripts.

[1]
Please refer to these code snippet:
ubuntu-recovery/ubiquity/ubuntu-bootstrap.py unset_drive_preseeds()
.
ubuntu-recovery/ubiquity/ubuntu-bootstrap.py:1290 → early = '/usr/share/ubuntu/scripts/oem_config.sh early %s %s' % (rec_part['device'], location)
.
ubuntu-recovery/casper/seeds/ubuntu.cfg:138 → d-i oem-config/late_command string /usr/share/ubuntu/scripts/oem_config.sh late